Composite floor construction utilizing welded studs



Jan. 1,6, 196s E. E. CURAN 3,363,379

COMPOSITE FLOOR CONSTRUCTlON UTYILIZING WELDED STUDS Filed 001'.. 6, 1965 HEPA/APD E Cl/R/V United States Patent Oce 3,363,37@ Patented lian. 16, i968 e, am...

ABSTRACT F THE DISCLOSURE A building floor construction utilizing sheet metal decking and providing composite co-action between the concrete and the structural beams of a building. The sheet metal decking rests on the structural beams and is secured thereto by plug welds or button welds. Generally vertical studs are fusion welded to selected ones of the plug welds. The studs serve as shear-transferring elements in the resulting floor construction.

This invention relates to composite door construction providing composite co-action between concrete and structural beams of the building with welded studs being secured to the building means as shear transfer elements. More particularly this invention is concerned with a novel method for introducing welded studs to a building structure utilizing sheet metal decking and to the improved resulting structure.

T he use of welded studs The use of welded studs for achieving composite coaction between a metal beam and a covering concrete slab has been in the prior art for some time. See Singleton Patent 2,987,855. Welded studs are normally factory applied to structural beams which are thereafter erected in bridges, multi-story buildings and the like. The use of welded studs in multi-story buildings utilizing sheet metal flooring sections has been unsuccessful in the past because ofthe added expenses which are incurred. Factory installed studs cannot be considered for the reason that the studs themselves interfere with the positioning of sheet metal ooring in the building which is equipped with factory installed studs on its horizontal beams. The presence of numerous exposed vertical studs throughout the entire building construction period of the building presents a continuing severe safety hazard to workmen.

Field installed studs are inherently more expensive than factory installed studs. Moreover the studs are only effective when they are structurally integral with the building framework, i.e., the beam itself. Accordingly it has been necessary to provide gaps in the ooring for shear connectors, U.S. 3,177,619, or to provide drilled, burned or punched holes in the sheet metal flooring at those locations where it is anticipated that welded studs will be required in order to provide direct Welding of the studs to the metal beam. With relatively light gauge sheet metal decking, recent developments in the welding arts permit direct welding of shear-transferring studs through the light-gauge decking directly into the horizontal beams. However with heavier gauge decking, eg., 16 gauge and thicker, and with double thickness metal cellular flooring sections, it is required to drill, burn or punch studreceiving holes in the decking to accommodate the welded studs. Such holes cannot be drilled or punched at the factory in an economical manner for the reason that the precise location of each decking section is not known at the time such sections are fabricated in a factory. Perhaps of greater importance is the dimensional variations in building construction. Building frames are assembled to a tolerance of about one-half-inch. Factory punched holes to accommodate such variations would be excessively large. Accordingly field punching or drilling of the decking sections is required with concomitant expense.

The present invention According to the present invention, I have observed that corrugated metal decking sections are traditionally fastened to the building framework by small fusion welds (sometimes called plug welds or button welds) directly between the decking sections and the subjacent supporting beam. These fusion welds form from small buttons of weld-metal about 1 inch in diameter. After the weld metal has had an opportunity to cool, any slag capping formation appearing on the Weld buttons is chipped away and the weld buttons are normally coated with corrosionresisting paint. The application of the fusion weld buttons to the building framework is relatively simply accomplished by a construction Workman with electric welding rods. The fusion weld buttons actually bite into the metal of the subjacent beam and becomes integral therewith.

The present invention consists in utilizing the fusion weld buttons as anchoring sites for welded studs which will serve as shear-transferring elements in the resulting building. The invention further consists in providing a substantial number of fusion weld buttons extending entirely through the sheet metal flooring directly into the top flange of the subjacent beams. The shear-transferring welded studs are then applied, one each, directly to the fusion weld buttons. The number of weld buttons required for this purpose may be in excess of the number heretofore required for merely securing the sheet metal decking to the steel framework.

Objects The objects of this invention include:

To provide a means for economically installing Welded shear-transferring studs in a building construction utilizing sheet metal decking sections;

To provide a composite building floor utilizing sheet metal decking, welded studs and concrete;

To provide a means for securing sheet metal decking in a building framework and to utilize that means for installing welded studs in shear-transferring relation with the building framework.

These and other objects and advantages of the present invention will become apparent from the following detailed description by reference to the accompanying drawings in which:

FIGURE 1 is a fragmentary illustration of a typical multistory building utilizing sheet metal decking;

FIGURE 2 is a fragmentary cross-section illustration of a door of the building shown in FIGUR-E l illustrating the use of welded studs as shear transferring members according to the present state of the art;

FIGURE 3 is a cross-section illustration taken along the line 3-3 of FIGURE 2 showing the use of Welded studs according to the present state of the art in the construction of buildings;

FIGURE 4 is a cross-section illustration showing a section of metal cellular flooring secured to a subjacent building beam by means of a typical fusion weld button;

FIGURE 5 is a cross-section illustration similar to FIGURE 4 showing the afxation of a welded stud directly to a fusion weld button in accordance with the present invention;

FIGURE 6 is a fragmentary perspective illustration of a typical corrugated sheet metal decking section spanning one beam and extending lengthwise above a crossbeam of a building floor.

As shown in FIGURE 1 a typical modern building 10 includes vertical columns 11 and horizontal beams 12.

Where metal decking is utilized, the decking is provided Yof shear transferring studs along each of the horizontal beams 12. In the past, the shear-transferring studs have been applied as shown in FIGURES 2 and 3. A horizontal beam 12 supports the sheet metal flooring 13 which is in the form of metal cellular ilooring having a corrugated upper sheet 2li and an essentially flat bottom sheet 21. 'Ihe corrugated upper sheet 2li has a plurality of alter- Vmating crests 22 and valleys 23 with intervening generally vertical webs 24. Holes 25 are punched,`drilled or burned into the valleys 23 of the sheet metal decking section 13 in order to expose a portion of the top flange of the supporting beam 12 to provide a site for the fusion Welding of the familiar shear-transferring studs 2e directly to the top flange of the beam 12.

Shear-transferring studs can be quickly applied at the building site through the holes 25 by means of electric arc stud welding equipment which consists of a welding gun which receives the stud. The loaded welding gun is positioned against the weld-site and actuated. An electric arc fuses the Weld-site metal. When the weld-site is properly molten, the gun plunges the stud into the molten puddle to achieve a rugged, secure stud attachment.

It is a common practice for sheet metal decking to be secured directly to a subjacent beam by fusion welding as shown in FIGURE 4. There a fusion weld button is illustrated as extending entirely through the valley 23 and Y x at bottom sheet 21 into the top ilange of the horizontal beam 12. Such fusion weld buttons are applied by a welding workman who touches the upper surface of the valley 23 with a welding rod and burns and rotates the end of the welding rod until he has burned entirely through the sheet metal of the deck to the top ange f the beam 12. During the course of this burning, a quantity of the metal from the welding rod is melted and fused with the melted metal from the sheet metal decking and with a portion of the metal from the top flange of the beam 12. All of the molten metal forms the fusion weld button 30 which extends slightly above the top surface of the valley 23. After the weld button 30 has cooled, a workman returns to the site and chips away any slag formation which may be presented on a button surface. Thereafter, according to existing practices, the weld bottom 3i) is coated with a corrosion-resistant paint. If any welded studs are to be atiixed to the resulting structure, suitable holes are drilled or burned through the sheet metal decking to accommodate the studs and to provide exposure of a suicient portion of the top flange of the beam 12 for this purpose.

According to my present invention as shown in FIG- URE 5, the shear-transferring studs 31 are welded directly to the weld button 30 whereby they become integral with the top flange of the beam 12 without the need for drilling or burning or punching extrinsic holes through the sheet metal decking to accommodate the studs.

In general the number of plug welds 30` required to support the sheet metal decking will be less than the number of shear transferring studs required for a composite floor construction. Accordingly, following the teachings Of my present invention, the building constructor will provide a number of fusion weld buttons Strwhich is in excess of that required merely to secure the metal decking to the beams 12. The excessive weld buttons will correspond in number and location to the welded studs required for achieving composite co-action between a concrete layer and the studs. This can be seen in FIGURE 6 where the transverse beams 12a extend at right-angles to the longitudinal beams 12b. The metal cellular flooring section 32 is secured to the transverse beams 12a by means of the described fusion weld buttons 36a which extend through the decking 32 directly to the top ilange of the transverse beam 12a. The lateral valley 33 of the metal ilooring section 32 rests upon the longitudinal beam 12b. A number of fusion weld buttons 34 is provided General comments It will be observed that the present invention requires separate welding operations to be performed at the building site for the assembly of a composite building door. The first welding operation provides a button of weld metal extending from a subjacent beam through a sheet metal decking section. The second welding operation involves the fusion welding of a generally vertical sheartransferring stud directly to the previously applied weld metal button.

I claim:

1. A building oor assembly including:

a horizontal metal beam;

a metal decking section secured to said beam;

a plug of weld metal formed by fusion welding said deck section to said beam, said plug extending from said beam through said metal decking section and being integral therewith to form a weld button above the metal sheet surface of the said decking section;

a generally vertical stud, fusion Welded to the said weld button. Y

2. A method of assembling a building lioor comprising:

(a) assembling corrugated sheet metal decking sections side-by-side on horizontal metal beams of a building framework;

(b) securing said decking sections to said beams by fusion weld buttons extending through said decking into said beams;

(c) aflixing generally vertical metal studs to said beams by welding the studs to selected ones of said fusion weld buttons;

(d) covering the said decking sections and said studs with concrete to provide a building iioor wherein the said concrete and the said beams co-act compositely.

References Cited UNITED STATES PATENTS 2,245,688 6/1941 Kruger 52-336 X 2,987,855 6/1961 Singleton et al. 52-334 3,177,619 4/1965 Benjamin 52-332 OTHER REFERENCES V American Concrete Institute lournahhereafter called the ACI Journal, TA 681.15161, November 1946, pp. 241H 248. l

Civil Engineering, TA l. C 61, October 1961, p 69` 70 FRANK L. ABBOTT, Primary Examiner.

ALFRED C. PERHAM, Examiner.

along the length of the valley 33 extending entirelyV 

